Slavery in Spain can be traced to the times of the Greeks, Phoenicians and Romans. In the 9th century the Muslim Moorish rulers and local Jewish merchants traded in Spanish and Eastern European Christian slaves. Spain began to trade slaves in the 15th century and this trade reached its peak in the 16th century. The history of Spanish enslavement of Africans began with Portuguese captains Antão Gonçalves and Nuno Tristão in 1441. The first large group of African slaves, made up of 235 slaves, came with Lançarote de Freitas three years later.[1] In 1462, Portuguese slave traders began to operate in Seville, Spain. During the 1470s, Spanish merchants began to trade large numbers of slaves. Slaves were auctioned at market at a Cathedral, and subsequently were transported to cities all over Imperial Spain. This led to the spread of Moorish, African, and Christian slavery in Spain. By the 16th century, 7.4 percent of the population in Seville, Spain were slaves. Many historians have concluded that Renaissance and early-modern Spain had the highest amount of African slaves in Europe.[2]

After the discovery of the New World, the Spanish colonialists decided to use it for commercial production and mining because of the absence of trading networks.[3] The native Indian population was used for this labor but they died in large numbers as a result of war, diseases, exploitation and social disruptions.[3] Meanwhile, the need for labor expanded, such as for the production of sugarcane.[3] The problem of the justness of Indian slavery was a key issue for the Spanish Crown. Bartolomé de las Casas was concerned about the fate of the natives and argued in 1516 that white and black slaves should be imported to the Indies to replace the Amerindians.[3] African slaves did have certain advantages over native slaves as being resistant to European diseases and more familiarity with agricultural techniques.[3] This preference led to the development of the Atlantic Slave Trade.[3] It was Charles V who gave a definite answer to this complicated and delicate matter. To that end, on November 25, 1542, the Emperor abolished the enslavement of natives by decree in his Leyes Nuevas New Laws. This bill was based on the arguments given by the best Spanish theologists and jurists who were unanimous in the condemnation of such slavery as unjust; they declared it illegitimate and outlawed it from America—not just the slavery of Spaniards over Indians—but also the type of slavery practiced among the Indians themselves[4] The labor system of Encomienda was also abolished in 1550.[3] However these laws did not end the practice of slavery or forced labor immediately and a new system of forced native Indian labor began to be used repartimiento and mita in Peru. Eventually this system too was abolished due to abuses.[3] By the 17th century, forced native Indian labor continued illegally and black slave labor legally.[3]

These slaves were used for services and employed in various ways such as employment “in domestics, artisans an assistance of all kinds”.[5] For a society to be considered a slave society there would need to be at “30% of the population as slaves, and slave labor had to account for a major proportion of that society’s production’.[6] So in the time frame of the Roman times to the Middle Ages the percentage of the slave population were minimal. “slaves probably made up less than 1 percent of the population in Spain”.[7] “Slavery was cross cultural and multi-ethnic” [8] in addition to that, slavery played an important role in the development of the economy for Spain and other countries.[9]

The idea that slavery was based on race was and continues to be one of the biggest misconceptions about slavery in Spain. Phillips Jr. William D. in The History of Slavery in Iberia, challenged the idea that race was not the key to determine who was enslaved, but instead religion. Roman laws existed, subjugating slavery which included the sources of slaves, their conditions, and possibility of liberation.[10] In addition, the "normal pattern" was to prohibit people from enslaving someone within their same religion.[10] Muslims could not enslave Muslims, Christians could not enslave Christians, and so on.

During the Al-Andalus (also known as Muslim Spain or Islamic Iberia), the Moors controlled much of the peninsula. They imported white Christian slaves from the 8th century until the end of the Reconquista in the late 15th century.[citation needed] The slaves were exported from the Christian section of Spain, as well as Eastern Europe, sparking significant reaction from many in Christian Spain and many Christians still living in Muslim Spain. As the Muslims followed the same technique as Romans to capture slaves; seeking cities to ally with them. Soon after, Muslims were successful, taking Christian captives of 30,000 from Spain. In the eighth century slavery lasted longer due to “frequent cross-border skirmishes, interspersed between periods of major campaigns.”. By the tenth century, in the eastern Mediterranean Byzantine Christian’s were captured by Muslims. Many of the raids designed by Muslims were created for a fast captive of prisoners. Therefore, Muslims restricted the control in order to keep captives from fleeing. The Iberian peninsula served as a base for further exports of slaves into other Muslim regions in Northern Africa.[11]

In 1442, Pope Eugene IV gave the Portuguese the right to explore Africa.[citation needed] The Portuguese attempted to protect their findings from the Spanish, who were beginning to explore Africa contemporaneously. At that time, Spain was occupied by a Muslim power and the Catholic Church felt threatened. Protecting the church, Pope Nicholas V in 1452 gave the right to enslave anyone who was not practicing the Christian religion, known as the Dum Diversas. The Spanish government created the Asiento system, which functioned between the years of 1543 and 1834. The Asiento allowed other countries to sell people into slavery to the Spanish. A population by the late 16th century was mostly composed of individuals of African descent.[12]Antumi Toasijé states in the Journal of Black Studies, "African peoples have an ancient presence in the Iberian Peninsula. In fact, Spanish identity especially has been forged on the frontlines of African and European interaction."[13]

The Moors often served as slaves in Christian Spain. These slaves were captured from Muslim Spain and North Africa and imported into the Christian section of the Iberian peninsula. When the Moors were forcibly evicted from Spain, in 1610, Moor slaves were allowed to stay, however, they were forced to convert to Christianity. Spain's Moorish slave population was eventually freed in the early 18th century.[14]

The treatment of slaves in Spain was thought[according to whom?] to be less harsh compared to other parts where slaves were held captive. Individual slaves of Muslims could over the time rise to a certain stature that could allow them to become free. However, the treatment of slaves differed with each slave owner, even though some laws protected slaves. For instance, “ the Qur’ān stated that slaves should be treated well, as did a Hadith attributed to Muhammad.”[9] As the owners’ of slaves they could sell or trade their slaves as they wished. Some examples of cruelty that occurred include beating of slaves and, depending on certain violations, slaves could be killed. In addition to the limited privileges of the Muslim slaves, they completely relied on their owners. “With no independent legal rights, slaves could not serve as witnesses in court, could not testify against their master, and could not initiate legal action on their own.”[9] The slave owners’ control was dependent on the notion that slaves would be harmful to their interests if they had more rights. It was also important to Spanish slave-owners that their slaves adopt Spanish names and accept Christianity as their religion. Spanish slaves who converted to Christianity were often treated less harshly, and had better opportunities to gain freedom.[15] As Christianity was the dominant faith in Spain, it was considered respectful for slaves to adopt this religion as their own and abandon their former religious beliefs. A willingness to comply with this conversion led to better treatment and a closer relationship between slaves and their owners. It also gave them a better chance of being accepted into Spanish society following their freedom. As punishment for bad behavior, they would force the slaves to drink harsh drinks.

Although slavery in Spain has existed prior to the Trans-Atlantic Slave Trade, it is important to see Spain's involvement of the trade. Spain's connection to the trade with Africa was minor with only 185 voyages and 61,000 slaves from the continent from 1500-1800. This compares to almost 25,000 voyages and over 7 million slaves embarked in total by all nations from 1500-1800. However, from 1800-1866, the Spanish increased their voyages to 1,500 and number of embarked slaves to over 470,000 from Africa.

Most of their slave involvement occurred in the Caribbean. Out of an estimated 514,000 slaves, 400,000 arrived in Cuba from the late 18th century to mid-1800's. Based on these statistics, one can analyze the Spanish interests in the slave trade as late behind those compared with other nations. Spanish colonization was the focus from 1500-1800 in the Americas. By 1800, Trans-Atlantic Slave Trade was slowly starting to decline, and Spain appeared to rush transporting slaves into Cuba, one of their biggest colonies. Through this, one can compare differences in ethnicity of former Spanish colonies as Cuba has a much higher African descent unlike Mexico which only appears to have received little to none before independence from Spain.[16]